PB1955: PROGNOSTIC VALUE OF SERUM CREATININE TO CYSTATIN C RATIO AND ESTABLISHMENT OF A NOVEL RISK SCORE MODEL IN CHRONIC LYMPHOCYTIC LEUKEMIA
Authors: Zixun Yin, Ming Liu, Junyun Yuan, Dai Yuan, Mei Ding, Xueling Ge, Xiaosheng Fang, Ya Zhang, Xin Wang
Journal: HemaSphere (2023)

Topic: 6. Chronic lymphocytic leukemia and related disorders - Clinical Background: Chronic lymphocytic leukemia is a B lymphocytes malignancy mainly in the middle-aged and elderly population with highly heterogeneous in pathogenesis, clinical course and therapy efficacy. Recent studies demonstrated that greater physical fitness in CLL seemed related to better disease control. Hence, the estimation of physical capacity in CLL patients is necessary. Nevertheless, indicators associated with physical ability were not included in common prognostic systems for CLL. Sarcopenia is konwn as an age-related syndrome and associated with dismal prognosis in several cancers. However, the assessment of sarcopenia is not easily available. Serum creatinine to cystatin C ratio (CCR) is a novel, easily accessible, yet reliable surrogate biomarker for sarcopenia and correlates with the survival of several cancers. To date, the prognostic role of CCR in CLL patients remains unknown. Aims: The study focused on the predictive value of CCR in CLL and established a novel risk stratification model for CLL patients. Methods: CLL patients diagnosed in the Department of Hematology in Shandong Provincial Hospital from October 2010 to June 2022 were included in the study. The χ2 test or Fisher’s exact test was used to analyze categorical variables. Receiver operating characteristic (ROC) curve was used to evaluate the optimal cut-off value of CCR. Univariate and multivariate cox regression analyses were conducted to assess the prognostic independence of clinical variables on overall survival (OS) and treatment-free survival (TFS). Kaplan-Meier method and log-rank tests performed the survival analysis. The prognostic capacities were measured by the corresponding areas under the curve (AUCs) of ROC curves. Results: A total of 627 CLL patients were included in the study and randomly allocated to a training cohort (n=439) and the validation cohort (n=188) in a ratio of 7:3. There was no significant discrepancy in clinical characteristics between the two cohorts. The optimal cut-off value of CCR was 0.613. Multivariate cox regression analyses demonstrated that CCR (p=0.047) were independent prognostic biomarkers of OS in CLL. The Kaplan-Meier curve presented the association of high CCR and longer OS in both the training cohort (p<0.001) and validation cohort (p=0.002) (shown in Figure 1). The ROC curves showed the superior prognostic value of CCR (AUC=0.657) compared to the Rai stage (AUC=0.608) and Binet stage (AUC=0.530) in the training cohort. Besides, the favorable discrimination ability of CCR (AUC=0.673) was shown in the validation cohort in comparison with the Rai stage (AUC=0.573) and Binet stage (AUC=0.540). Combining CCR and CLL-IPI, a new risk stratification system was developed, named CLL-IPI-CCR. The CLL-IPI-CCR score system stratified patients into 4 risk groups: Low risk (0-1 point), intermediate risk (2-4 points), high risk (5-8 points) and very high risk (9-11 points). Our results demonstrated that CLL-IPI-CCR surpassed CLL-IPI in prognostic accuracy (shown in Figure 2). Summary/Conclusion: CCR appears be a good candidate for predicting OS in CLL and optimizing the risk stratification of CLL patients. Keywords: Chronic lymphocytic leukemia, Prognosis